A downhole video acquisition device monitoring operation method

Abstract

The application discloses a kind of well video acquisition equipment monitoring operation methods.There is comprising: according to the perforation section length of target horizontal well and total hole number, determine the shooting estimated length of video acquisition equipment to the perforation section monitoring operation of target horizontal well;According to the first predetermined shooting time point, shooting estimated length and target horizontal well well shut-in pressure drop rate data, determine the first operation minimum pressure value of video acquisition equipment to the perforation section monitoring operation;When the first operation minimum pressure value is less than or equal to the fracture closure pressure value of target horizontal well, water injection energy supplement operation is carried out to target horizontal well, so that the first operation minimum pressure value is greater than the fracture closure pressure of target horizontal well;Video acquisition equipment is transported to the perforation position of target horizontal well, and video shooting is carried out at least from the first predetermined shooting time point.The application can effectively solve the problem that screen is blocked by returned fluid in horizontal section position of downhole television.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of oil production engineering, and in particular, relates to a downhole video acquisition device monitoring operation method. BACKGROUND

[0002] With the continuous innovation of fracture monitoring means, fracture characterization technology gradually moves towards more refinement and more accuracy, and horizontal well volume fracturing technology has achieved good results in the development of shale oil and gas reservoirs. The commonly used fracture monitoring means currently include microseismic, optical fiber, tracer, downhole television, etc. Different monitoring means have different principles and advantages. Among them, downhole television is a monitoring means that directly obtains real-time video images downhole by using a high-temperature and high-pressure downhole camera and a logging cable high-speed transmission system. Through image enhancement, transformation, calibration, quantitative analysis, target identification, real scene modeling and other related processing, real and reliable wellbore information is obtained, and the uncertainty of downhole conditions is eliminated. Downhole television is widely used and can monitor oil casing integrity, find water and leaks, monitor production fluid profile, etc. In the aspect of hydraulic fracturing, it is mainly used to monitor perforation hole erosion and evaluate multi-cluster uniformity.

[0003] However, in the actual monitoring process of downhole television, due to the serious filtration loss of slick water fracturing fluid, the bottom hole pressure is below the closure pressure, the formation fluid returns, and the screen of the downhole television at some positions in the horizontal section is blocked by the returned fluid, which affects the smooth development of the monitoring work and reduces the success rate of the monitoring operation. SUMMARY

[0004] The purpose of the present application is to overcome the shortcomings of the prior art and provide a downhole video acquisition device monitoring operation method, which avoids the problem of screen blocking by returned fluid at some positions in the horizontal section of the downhole television and improves the success rate of downhole television monitoring.

[0005] To achieve the above purpose, the following technical solutions are adopted in the present application:

[0006] A downhole video acquisition device monitoring operation method, comprising the following processes:

[0007] S1, determining the shooting estimated duration of the video acquisition device for the perforation section monitoring operation of the target horizontal well according to the perforation section length of the target horizontal well;

[0008] S2, determining the first operation minimum pressure value of the video acquisition device for the perforation section monitoring operation according to the first predetermined shooting time point of the video acquisition device, the shooting estimated duration and the pressure drop rate data of the target horizontal well;

[0009] S3, when the first operation minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, water injection energy supplement operation is performed on the target horizontal well to make the first operation minimum pressure value greater than the fracture closure pressure of the target horizontal well; when the first operation minimum pressure value is greater than the fracture closure pressure value of the target horizontal well, S4 is performed;

[0010] S4, the video acquisition device is transported to the perforation section of the target horizontal well, video shooting is started from the first predetermined shooting time point, and first video data is obtained.

[0011] Preferably, in S1, the total length of the perforation section of the target horizontal well is determined according to the horizontal section length and the perforation hole position of the target horizontal well.

[0012] Preferably, the specific process of S2 is: the minimum pressure calculation value of the video acquisition device for the perforation section monitoring operation is obtained according to the shooting estimated duration and the pressure drop rate data of the target horizontal well shut-in; and the first operation minimum pressure value of the video acquisition device for the perforation section monitoring operation is determined according to the minimum pressure calculation value and the preset additional pressure value.

[0013] Preferably, the preset additional pressure value ranges from 1 to 2 MPa.

[0014] Preferably, in S3, well flushing operation is performed on the horizontal well before the water injection energy supplement operation is performed on the target horizontal well.

[0015] Preferably, in S4, when it is judged according to the first video data that the screen of the video acquisition device is shielded, the water injection energy supplement operation is performed again on the target horizontal well;

[0016] The video acquisition device is transported to the perforation section of the target horizontal well to perform video shooting, and second video data is obtained.

[0017] Further, the process of performing the water injection energy supplement operation again is: the value of the preset additional pressure value is increased, and the second operation minimum pressure value of the video acquisition device for the perforation section monitoring operation is determined according to the first predetermined shooting time point of the video acquisition device, the shooting estimated duration, the pressure drop rate data of the target horizontal well shut-in, and the increased preset additional pressure value;

[0018] The water injection energy supplement operation is performed on the target horizontal well to make the second operation minimum pressure value greater than the fracture closure pressure of the target horizontal well.

[0019] Preferably, in S4, when it is judged according to the first video data that the screen of the video acquisition device is not shielded, the real-time measurement of the bottom hole pressure of the target horizontal well is obtained.

[0020] According to the real-time measurement of the bottom hole pressure of the target horizontal well and the fracture closure pressure of the target horizontal well, it is determined whether to perform the well opening and blowout operation.

[0021] Preferably, in S3, a small-scale fracturing test is performed on the target horizontal well to obtain test data of the target horizontal well; and the test data of the target horizontal well is analyzed by using a G-function curve analysis method to obtain a fracture closure pressure value of the target horizontal well.

[0022] Preferably, in S3, the fracture closure pressure value of the target horizontal well is obtained according to the fracture closure pressure value of at least one adjacent well; and the adjacent well is a horizontal well located in the same block as the target horizontal well.

[0023] Compared with the prior art, the present application has the following beneficial effects:

[0024] According to the total length of the perforation section of the target horizontal well, the present application determines the shooting estimation duration of the video acquisition device for the perforation section monitoring operation of the target horizontal well; according to the first predetermined shooting time point of the video acquisition device, the shooting estimation duration and the pressure drop rate data of the target horizontal well, the first operation minimum pressure value of the video acquisition device for the perforation section monitoring operation is determined; when the first operation minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, water injection energy supplement operation is performed on the target horizontal well, so that the first operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well; the video acquisition device is delivered to the perforation position of the target horizontal well, and video shooting is performed at least from the first predetermined shooting time point to obtain first video data; the present embodiment realizes the adjustment of the bottom hole pressure, and at the same time achieves the purpose of the bottom hole pressure being greater than the closure pressure and improving the inter-section pressure balance degree, solves the problem of the return of the formation fluid blocking the screen, and thus improves the success rate of the downhole television monitoring. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The present application is a downhole video acquisition device monitoring operation method flowchart. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application; based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0027] It should be noted that the words "front", "back", "left", "right", "up" and "down" used in the following description refer to the directions in the drawings, and the words "in" and "out" refer to the directions towards or away from the geometric center of a particular component.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. The use herein of the terms "and / or" includes a set of one or more associated listed items.

[0029] Embodiment 1

[0030] As shown in the embodiment, the method for monitoring the operation of the downhole video acquisition device comprises the following steps: Figure 1

[0031] In step S10, the shooting estimated duration of the video acquisition device for monitoring the operation of the perforation section of the target horizontal well is determined according to the length of the perforation section of the target horizontal well.

[0032] In this embodiment, the target horizontal well to be monitored is selected, and the length of the perforation section is obtained, so that the shooting estimated duration required after the video acquisition device is lowered can be obtained, thereby improving the efficiency and saving resources.

[0033] Optionally, the total length of the perforation section of the target horizontal well is determined according to the length of the horizontal section of the target horizontal well and the total number of perforation holes of the perforation section.

[0034] The total length of the perforation section of the target horizontal well can be obtained by the length of the horizontal section of the target horizontal well and the total number of perforation holes of the perforation section.

[0035] In step S20, the first operation minimum pressure value of the video acquisition device for monitoring the operation of the perforation section is determined according to the first predetermined shooting time point of the video acquisition device, the shooting estimated duration and the pressure drop rate data of the target horizontal well.

[0036] In this embodiment, when the video acquisition device performs the monitoring operation on the perforation section, the pressure at the bottom of the well needs to be greater than or equal to the first operation minimum pressure value, which is determined by the first predetermined shooting time point of the video acquisition device, the shooting estimated duration and the pressure drop rate data of the target horizontal well.

[0037] Optionally, determining the first operation minimum pressure value of the video acquisition device for monitoring the operation of the perforation section according to the shooting estimated duration and the pressure drop rate data of the target horizontal well comprises: obtaining the minimum pressure calculation value of the video acquisition device for monitoring the operation of the perforation section according to the shooting estimated duration and the pressure drop rate data of the target horizontal well; and determining the first operation minimum pressure value of the video acquisition device for monitoring the operation of the perforation section according to the minimum pressure calculation value and a preset additional pressure value.

[0038] ​The first operation minimum pressure value of the perforation section monitored by the video acquisition device is determined by a minimum pressure calculation value and a preset additional pressure value, the minimum pressure calculation value is determined by the shooting estimated time length and the pressure drop rate data of the target horizontal well, and the preset additional pressure value is added to ensure that the fracture does not close during shooting, thereby improving the success rate of the operation.

[0039] Further, the preset additional pressure value ranges from 1 to 2 MPa.

[0040] The preset additional pressure value is set to offset the influence of the deviation of the first operation minimum pressure value of each section caused by the reservoir heterogeneity.

[0041] In step S30, when the first operation minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, water injection energy supplement operation is performed on the target horizontal well, so that the first operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well.

[0042] In this embodiment, the first operation minimum pressure value needs to be greater than the fracture closure pressure of the target horizontal well when the video acquisition device is shooting. If the first operation minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, water injection energy supplement operation needs to be performed on the target horizontal well.

[0043] Optionally, before the water injection energy supplement operation is performed on the target horizontal well, well flushing operation is performed on the horizontal well. By performing well flushing operation on the horizontal well and then performing water injection energy supplement operation, the bottom hole pressure is greater than the fracture closure pressure value of the target horizontal well, which can ensure that the shooting is clear.

[0044] The function of water injection energy supplement is to make the pressure at each perforation greater than the closure pressure, so that oil, sand and other substances in the fracture cannot enter the wellbore, and to promote pressure balance between sections.

[0045] The method for obtaining the fracture closure pressure value of the target horizontal well can be more direct and accurate by performing small-scale fracturing test on the target horizontal well, and analyzing the test data of the target horizontal well by using G function curve analysis method to obtain the fracture closure pressure value of the target horizontal well.

[0046] If the target horizontal well has not carried out small-scale fracturing test, the fracture closure pressure value of the target horizontal well is obtained by converting the fracture closure pressure gradient obtained from the small-scale fracturing test of the adjacent well in the same block, which can realize lower construction cost under the premise of ensuring the accuracy of the fracture closure pressure value, and the adjacent well is the horizontal well located in the same block as the target horizontal well.

[0047] Step S40, deliver the video acquisition device to the perforation section depth through the coiled tubing, complete the acquisition of all the perforations. If the phenomenon of screen being blocked still occurs during the acquisition process, it indicates that the additional pressure selected is too small, increase the original additional pressure, recalculate the required pressure at the wellhead, reflush, supplement energy, and then lower the coiled tubing to carry the downhole video to monitor the perforation shape until all the perforations are recorded.

[0048] Specifically, the video acquisition device is delivered to the perforation section of the target horizontal well, and video shooting is performed at least from a first predetermined shooting time point to obtain first video data.

[0049] In this embodiment, the video acquisition device is lowered into the perforation section of the target horizontal well to perform video shooting at least from a first predetermined shooting time point to obtain first video data.

[0050] Optionally, when it is judged according to the first video data that the phenomenon of screen being blocked occurs, water injection and energy supplement operation is performed again on the target horizontal well; the video acquisition device is delivered to the perforation section of the target horizontal well to perform video shooting and obtain second video data.

[0051] If the phenomenon of screen being blocked occurs during the video shooting, it indicates that water injection and energy supplement operation needs to be performed again on the target horizontal well, which can make the pressure at each perforation greater than the fracture closure pressure, so that oil, sand and the like in the fracture cannot enter the wellbore, and promote pressure balance between sections and reduce the influence of reservoir heterogeneity.

[0052] Further, when it is judged according to the first video data that the phenomenon of screen being blocked occurs, the water injection and energy supplement operation performed again on the target horizontal well includes: increasing the value of the preset additional pressure value, and determining a second operation minimum pressure value of the video acquisition device for the monitoring operation of the perforation section according to the first predetermined shooting time point of the video acquisition device, the shooting estimated duration, the pressure drop rate data of the target horizontal well during well blanking, and the increased preset additional pressure value; and performing water injection and energy supplement operation on the target horizontal well, so that the second operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well.

[0053] To avoid the phenomenon of screen being blocked, the value of the preset additional pressure value needs to be increased, and the second operation minimum pressure value of the video acquisition device for the monitoring operation of the perforation section is adjusted according to the first predetermined shooting time point of the video acquisition device, the shooting estimated duration, the pressure drop rate data of the target horizontal well during well blanking, and the increased preset additional pressure value, so that the second operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well, and the subsequent shooting is ensured to be normal.

[0054] Optionally, after the completion of the operation, when it is judged according to the first video data that the screen of the video acquisition device is not blocked, the real-time measurement of the bottom hole pressure of the target horizontal well is obtained; and whether the well opening and blowout operation is performed is determined according to the real-time measurement value of the bottom hole pressure of the target horizontal well and the fracture closure pressure of the target horizontal well.

[0055] Wherein, when the screen of the video acquisition device is not blocked, the real-time measurement of the bottom hole pressure of the target horizontal well is obtained, and the fracture closure is judged and the subsequent operation is adjusted in combination with the fracture closure pressure of the target horizontal well.

[0056] Wherein, the bottom hole pressure value can be obtained by converting the wellhead pressure value.

[0057] If the wellhead pressure shows that the formation fracture is not closed, the well is continued to be closed until the fracture is closed, and the well is opened and blown out. If the wellhead pressure shows that the formation fracture has been closed, the well is directly opened and blown out.

[0058] As can be seen from the above embodiment, the present application determines the shooting estimation duration of the video acquisition device for the perforation section monitoring operation of the target horizontal well according to the perforation section length of the target horizontal well; determines the first operation minimum pressure value of the video acquisition device for the perforation section monitoring operation according to the first predetermined shooting time point of the video acquisition device, the shooting estimation duration and the pressure drop rate data of the well closing of the target horizontal well; when the first operation minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, performs the water injection energy supplement operation on the target horizontal well, so that the first operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well; transports the video acquisition device to the perforation section of the target horizontal well, and starts video shooting from at least the first predetermined shooting time point to obtain the first video data; adjusts the bottom hole pressure, and achieves the purpose of the bottom hole pressure being greater than the closure pressure and improving the inter-section pressure balance degree, solves the problem of the screen being blocked by the return of the formation fluid, and further improves the success rate of the downhole television monitoring.

[0059] Embodiment 2

[0060] The present embodiment provides a downhole video acquisition device monitoring operation method, which comprises the following specific steps:

[0061] In order to explore the liquid inlet conditions of each cluster in the section and the erosion conditions of the perforation hole in the perforation process, the downhole high-definition video imaging monitoring of H1 well after the horizontal well segmented multi-cluster fracturing is carried out, the hole parameter and image at different perforation positions in the horizontal section are obtained, the change of the perforation hole shape and size before and after fracturing is analyzed, the opening degree and reconstruction effect of different perforation clusters are evaluated, and the guidance basis for the optimization design of the horizontal well volume fracturing is provided.

[0062] Step 1: H1 well is a horizontal well, the completion layer is Chang 71 layer, the completion depth is 3267m, the vertical depth is 1700m, the DMS soluble ball seat segmented multi-cluster fracturing technology is used for fracturing reconstruction, a total of 23 segments are fractured, a small-scale fracturing test is carried out before fracturing the first segment, and the calculated closure pressure is 23.8MPa, the converted wellhead pressure is 6.8MPa, affected by the working system, H1 well is muffled for a long time after fracturing, the wellhead pressure is reduced to 4MPa (lower than the closure pressure), so the wellbore is directly treated with continuous oil carrying pressure after muffle.

[0063] Step 2: The horizontal section of H1 well is 1300m long, a total of 23 segments are cleaned, and the estimated wellbore treatment operation time is 3 days. According to the pressure drop curve of H1 well after muffle, the pressure drop rate is about 1MPa / d, therefore, in order to ensure that the bottom hole pressure is always greater than the closure pressure during the operation, the minimum pressure required at the wellhead is predicted to be 9MPa.

[0064] Step 3: Coiled tubing circulation washing, after circulating and washing twice at 1900m-3100m, the fixed point is set to 3100m, and the liquid in and out is flushed to the wellhead, the returned fluid is placed in a bucket, and the effect is tested and recorded by using downhole video instrument, which can clearly see the handwriting of the card to indicate that the washing is qualified; then clean water is injected into the well, and the wellhead pressure change is monitored in real time, and the water injection is stopped when the wellhead pressure reaches 9MPa.

[0065] Step 4: The video acquisition device is transported to the depth of the first perforated segment by continuous oil, the first segment hole shape is recorded, then the second segment is recorded by back dragging, and all the segment hole recording is completed.

[0066] Step 5: After the downhole television monitoring operation is completed, the wellhead pressure is 8MPa, which is still 1.2MPa higher than the closure pressure, the well is continued to be muffled until the fracture is closed, and the well is opened for blowout.

[0067] It should be noted that in this text, relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or equipment.

[0068] It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the technology should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The omission in the foregoing description of any aspect of the subject matter disclosed herein is not a disclaimer of such subject matter, nor should it be regarded that the applicant has disclaimed any such subject matter, nor should any such omission be regarded as affecting the scope of the claimed teaching.

Claims

1. A method for monitoring operations using downhole video acquisition equipment, characterized in that: The following processes are included: S1, determining an estimated duration of video acquisition equipment for monitoring the perforation section of the target horizontal well based on the perforation section length of the target horizontal well; S2, determining a first minimum operating pressure value for the perforation section monitoring operation of the video acquisition device based on a first predetermined shooting time point of the video acquisition device, an estimated shooting duration, and the pressure drop rate data of the target horizontal well; S3: When the first operating minimum pressure value is less than or equal to the fracture closure pressure value of the target horizontal well, perform water injection and energy replenishment operations on the target horizontal well to make the first operating minimum pressure value greater than the fracture closure pressure of the target horizontal well; when the first operating minimum pressure value is greater than the fracture closure pressure value of the target horizontal well, proceed to S4; S4, transporting the video acquisition device to the perforation section of the target horizontal well, starting video shooting from a first predetermined shooting time point, and obtaining first video data.

2. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S1, the total length of the perforation section of the target horizontal well is determined based on the length of the horizontal section of the target horizontal well and the positions of the perforation holes.

3. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: The specific process of S2 is as follows: based on the estimated shooting time and the pressure drop rate data of the target horizontal well, the minimum pressure calculated value of the video acquisition equipment for the perforation section monitoring operation is obtained; based on the minimum pressure calculated value and the preset additional pressure value, the first operating minimum pressure value of the video acquisition equipment for the perforation section monitoring operation is determined.

4. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: The preset additional pressure value range is 1-2MPa.

5. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S3, before performing water injection and energy replenishment operations on the target horizontal well, a well flushing operation is performed on the horizontal well.

6. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S4, when it is determined based on the first video data that the screen of the video acquisition device is blocked, water injection and energy replenishment operations are performed again on the target horizontal well; The video acquisition device is transported to the perforation section of the target horizontal well to shoot a video and obtain second video data.

7. The method for monitoring downhole video acquisition equipment according to claim 6, characterized in that: The process of performing the water injection recharge operation again is as follows: increasing the value of the preset additional pressure value, and determining the second minimum operating pressure value of the video acquisition device for the perforation section monitoring operation based on the first predetermined shooting time point of the video acquisition device, the estimated shooting duration, the pressure drop rate data of the target horizontal well, and the increased preset additional pressure value; Perform water injection and energy replenishment operations on the target horizontal well so that the second operation minimum pressure value is greater than the fracture closure pressure of the target horizontal well.

8. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S4, when it is determined based on the first video data that the screen of the video acquisition device is not blocked, a real-time measurement of the bottom hole pressure of the target horizontal well is obtained; Determine whether to open the well and perform blowout operations based on the real-time measured bottom hole pressure of the target horizontal well and the fracture closure pressure of the target horizontal well.

9. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S3, a small-scale fracturing test is performed on the target horizontal well to obtain test data of the target horizontal well; the test data of the target horizontal well is analyzed using a G function curve analysis method to obtain a fracture closure pressure value of the target horizontal well.

10. The method for monitoring downhole video acquisition equipment according to claim 1, characterized in that: In S3, the fracture closure pressure value of the target horizontal well is obtained based on the fracture closure pressure value of at least one adjacent well; wherein the adjacent well is a horizontal well located in the same block as the target horizontal well.

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